Currently there are two popular methods of stabilizing a rifles buttstock. One is the sand sock and the other is a threaded bolt device that is used to raise and lower the rifle buttstock.
In the sand sock method a sock or cloth bag is filled with sand or beads to the desired level for a soft or hard support, usually one of each. The sock/socks are placed under the buttstock of the rifle with the non-shooting hand. The rifle is rested on the socks at the desired level to acquire a target. If the rifles barrel needs to be raised for targets further away the shooter releases his grip on the sock allowing the buttstock of the rifle to lower. If the barrel of the rifle needs to be lower the shooter increases his grip on the sock pushing the buttstock up.
The threaded bolt device for lowering and/or raising the buttstock employs bolt device that is fixed on the rifle. It is a threaded bolt screwed into a cylinder with a base plate at the bottom. This device is worked by twisting the cylinder around the bolt and lowering or raising the rifle buttstock.
A brief review of the prior art follows.
U.S. Pat. No. 6,860,054 discloses a pneumatic gun alignment system for accurately adjusting a gun position. The pneumatic gun alignment system includes a support bag having an air bag positionable beneath a firearm, and an air supply fluidly connected to the air bag for supplying pressurized air to the air bag. A valve unit is preferably positioned within the hose for allowing the user to slowly release air from the air bag and for maintaining a desired amount of air within the air bag. The user increases the air pressure to elevate the firearm and decreases the air pressure to lower the firearm.
U.S. Pat. No. 4,409,751 discloses a firearm support for holding and steadying a small arm such as a rifle. The firearm support includes a barrel support for supporting the barrel end of the firearm, a stock support for supporting the stock of the firearm and at least one adjustable slider rod interconnecting the barrel support with the stock support.
U.S. Pat. No. 5,819,461 describes an apparatus that helps a user to steadily hold a pointable device, such as a camera, a telescope, or a gun. It includes an arm rest having upper and lower portions, respectively, for supporting an upper arm from below and for restricting rotation of a lower arm bent at the elbow. The upper and lower arm holding portions each can press against a user's arm from enough directions to retard motion of the arm perpendicular to its length. The upper and lower portions can include cylindrical inner surfaces angled to bend an arm at least sixty degrees at the elbow. A support holds the arm rest from below. The support can include a rigid elongated member. In some embodiments, this member reaches to the ground. In many others, it rests against a user's hip and has a lower end designed to be supported by a pocket, belt, or Velcro pad on the user's hip. It is preferred that the elongated member slant down and in toward the hip from the arm rest at an adjustably fixed angle and that the lower arm holding portion be supported in a diagonal direction which points both up and in toward a position in front of the user's face. The apparatus often includes a mounting for the pointable device, preferably one which can be rotated with two degrees of freedom, and one the height of which relative to the arm rest can be adjustably fixed.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.